How do I jump from one time to another without confusing the reader?

Sometimes, the direct route is the best:

Later they danced.

Three months passed before Jim saw Shelly again.

In late spring of 1982, she took a train west.

With novels that are particularly sweeping in time and place, some authors will use headings to indicate the shift, as Kiana Davenport does in Song of the Exile: “Honolulu, mid-1930s.” Don’t let headings stand in for setting, though. It’s still important to create a sense of place and time.

The direct route isn’t always the best choice. Used too often, it can feel repetitious. Sometimes it’s even awkward, like when the jump takes place in a character’s thoughts:

She stood at the window, thinking back twenty years to the day her father left.

In this case, a trigger can help make the transition smoother:

Outside, two sparrows hopped from branch to branch, shaking the broad leaves. When they stilled, it was as if they’d not been there at all. She knew this sort of invisibility. She’d been climbing the old crab apple tree the afternoon her father left.

Almost anything can be a trigger. Mary Gaitskill used a character’s habit of stroking his nose hairs in “Tiny Smiling Daddy” to move back in time and chart the change in his daughter through her reactions to his habit as she grew up.

Don’t forget the power of well-written summary to ferry the reader thought days, seasons, and even years. In Davenport’s Song of the Exile, Keo, a budding musician has been invited to go to New Orleans to play, but he’s insecure about it:

DeSoto arranged his working passage on a freighter through the Panama Canal. His friends from the Royal took up a collection. Keo lost his nerve, returned the money, canceled all his plans.

Time has clearly passed and so has Keo’s confidence, and that’s one great benefit of summary: you can use it to give a glimpse of what happens in between the jumps.